The Prime Minister had hoped to secure a deal earlier this week, but had to row back after the DUP said they would not accept a draft deal that suggested “regulatory alignment” between Northern Ireland and the Republic.

At a press briefing this morning, Commission spokesman Margaritas Schinas made clear that the final deadline for the UK was this Sunday.

“We stand ready to receive Prime Minister May at any moment in time when they’re ready,” he told reporters.

“This will have to happen this week. In this building, we work for a full week, 24/7, and our week includes Sunday.”

A Number 10 spokesman sounded an optimistic note this morning, telling reporters: “We are close to an agreement but there is ongoing work still to be done and it is an ongoing process.”

Elsewhere Foreign Secretary Boris Johnson made clear that whatever solution is on the table must be consistent with the Leave campaign’s promises to voters.

"It is very, very important that whatever happens now, whatever we agree, has got to be consistent with taking back control of our laws, of our borders and our cash,” he said after a speech in Westminster.